Electric motor



Jan. 3, i950 c. NEHRKE 2,493,982

ELECTRIC MOTOR Filed April 23, 1947 CHARLES NEHRKE,

INVENTOR ATTO RNEY Patented Jan. 3, 1950 l TED S TAT ES PA'E'EN 'i' @E F ICE rfELEoTRIo Moron ,charles Nehrke, New verk, N. y.

v"Application April23, 1947, Serial Nc. 743,360

(o1. rra-3e) This invention relates lto `imprcmements inmotors, and more particularly does it relate to low voltage and low current electric motors.

An object of this invention is to provide an electric motor of the type described, which may be electrically energized by low voltage and low current dry batteries, such as are commonly used in flashlights.

Another object of this invention resides in the inclusion therein of detachable commutator contact members which are held in frictional contact with the commutator segments of the motor, and which may be readily removed for cleaning or other purposes.

A still further object of this invention is the provision of an organization in which the constituent elements are so arranged structurally and functionally as to assure improved results with materials and members which may be manufactured at reasonable cost, may be easily assembled and which will be eiiicient in operation with minimum wear to the parts.

This invention possesses other objects and features of advantage some of which, with the foregoing, will be set forth in the following description and in the claims wherein parts will be identied by specific names for convenience, but they are intended to be as generic in their application to similar parts as the art will permit. In the accompanying drawings, there has been illustrated the best embodiment of the invention known to me, but such embodiment is to be regarded as typical only of many possible embodiments, and the invention is not to be limited thereto.

The novel features considered characteristic of my invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and its method of operation, together with additional obj ects and advantages thereof, will best be understood from the following description of a specific embodiment when read in connection with the accompanying drawings, in which:

Figure 1 is an elevational view of the front end of the motor, and shows portions broken away.

Figure 2 is a longitudinal, sectional view of same, taken along the line 2--2 of Figure 1.

Figure 3 is an elevational View of the rear end of the motor, and has portions broken away.

Figure 4 is an end view of the rotor, showing one of the coil windings in section.

Figure 5 is a detail of a part carrying commutator contact members.

Referring in detail to the parts, I I designates a housing which carries, at its lower end, a permanent magnet i2, which, with the housing II,=is held upon a cup-shaped base member I3, by means of the screws i4. The said cup-shaped base member i3, is formed at one end with a short upright element I5, to which is secured, by means of the screws i5, an end plate I1, of suitable insulating material The opposite end of the Said cup-shaped base member I3, is formed with a longer upright element I8, extending upwardly to carry one end of a shaft I9, of a rotor 20.

The upright end element I8, is formed with a recess portion 2i, within which an oilless bearing 22, is seated and through which the shaft I9, engages. The said bearing 22, is held in place by means of a plate 23, secured to the upright end I8, by the screw 24, the said plate 23 having a right angle slotted tongue 49 and being slightly offset as at 25, to form a pocket which holds in place a packing element 26, of felt or other suitable material. A second offset 21, perforated as at 23, is formed upon the plate 23, and is adapted to hold the said oilless bearing 22, in place.

The rear end of the rotor shaft i9, is slightly reduced in diameter to form a bearing 29, which engages through the aforesaid insulator plate I'I.

Metallic carrier plates 39, having projecting lips 3l which extend through perforations 32, in the said insulator plate I'I, are held upon the said insulator plate and carry frictional contact members 33, which are, in turn, mounted in perforations 34, upon the said carrier plates 30. The said contact members 33, are formed with elongated commutator contact members 35, which frictionally engage commutator segments 36, of the rotor 2i). To keep the said commutator contact members 35, normally in engagement with the said. commutator segments, there are provided springs 3l, the opposite ends of which engage hook projections 38, formed upon the said frictional contact members 33.

The rotor 2U, consists of the said shaft I9, to which securely attached a spider-shaped arma.- ture frame 39; and the coils 40, wound upon the said spider, one of which is shown in section (Figure 4), an armature bushing 4I, disposed between the shaft IS, and the spider carrying the coils 40; a second bushing 42 termed the commutator bushing, mounted upon the shaft I9 (Figure 2) commutator segments 36, having insulating dividing strips 43; a sleeve 44, of suitable insulating material which engages over the said commutator segments and holds same together; and spacer sleeves 45 and 46, around the said shaft I9, disposed between the oilless bearing 22, and the bushing 4I, on one side and the commutator bushing 42, and the said bushing 4|, on the other side respectively. A base block 41, may be provided and secured to the housing I 3, by means of screws 48.

Electric conductors (not shown) may be attached to the said projecting lips 3l, to supply electric current to the commutator for operating the motor.

Iclaim:

1. An electric motor comprising a base member, a permanent magnet secured in said base member, an upright bearing element secured to the said base member, a second upwardly extending bearing element secured to the said base member, a rotor having a multiplicity of coils mounted in said upwardly extending bearing elements, a commutator upon said rotor, commutator contact members removably mounted upon one of said bearing elements and means removably attached to said bearing adapted to make connection with an electrical source, the said commutator members being fulcrumed upon '4 carrier plates removably mounted upon said bearing element.

2. An electric motor as set forth in claim 1, wherein the said commutator contact members are removably mounted and fulcrumed upon said bearing element and are formed with hook pro- J'ections adapted to engage a spring element to keep the said Contact members in frictional contact with the said commutator of the rotor.

CHARLES NEI-IRKE.

REFERENCES CITED The following references are of record in the ille of this patent:

UNITED STATES PATENTS Number Name Date 427,235 Ingraham May 6, 1890 498,585 Still May 30, 1893 2,102,347 Arnold Dec. 14, 1937 2,334,153 Wilson Nov. 9, 1943 

